The motion of the crank is transferred via the gear drives. This way the dynamo rotates fast enough to make the LED light up as brightly as a flashlight
Experiment with the mysterious elemental forces of the magnet and with the opposing forces of two magnets: Attraction and repulsion, magnetic pendulum or compass. How is a chain of nails formed? How do iron filings show the magnetic field? What does a double magnetic field look like?
The electromagnet is a special magnet: It can be switched on and off. With this knowledge, you can build a motor or a dynamo.
